Links for Writing Better Online

Accessify's Accessible Table Builder helps build HTML tables
WebAIM's Color Contrast Checker
WebAIM's WAVE Web Accessibility Tool
Color Hex Codes isn't strictly an accessibility tool. You can use it to find shades and tints of particular colors, so you can keep your site's theme/feel but with colors that have better contrast.

Presentation Tools:

• Hakim El Hattab's Reveal.js makes presentations accessible in various ways, especially if you use the plug-in below
• Marcy Sutton's reveal-a11y plugin hides Reveal.js's offscreen slides & improves accessibility for keyboard and screen reader users

De-jargonizer
Hemingway Editor
Readable.io will calculate readability test scores if you copy & paste in the text. Also explains many of the tests and score results.
Readability Test Tool will calculate readability test scores by url, by direct input/copy & paste, or by adding their link to one of your web pages.

HTML special character codes lists (& guide) from Penn State

Dillinger online markdown editor/converter
LaTeX Base online LaTeX editor/compiler
Mergely diff documents online
Try Pandoc

"How To"-style Guides:

• WebAIM's Web Accessibility for Designers
• Mozilla's Accessibility guide

Explainer-style Guides:

• Axess Lab's Trends that Exclude
• Axess Lab's Statistics on Disabilities

WebAIM's Writing Clearly and Simply

Programming Historian's Sustainable Authorship in Plain Text using Pandoc and Markdown

Here are more authoritative & exhaustive lists:

• Marcy Sutton's fork of a11y-resources
• Or see Atalan's original)

This is mostly just a lightly-annotated set of links to tools and guides about writing well for the web.

I mostly made this to keep these links handy from any computer I find myself using. You're welcome to use & add to it as well!